PLATE 21. 



Figs. 1-6. .Mexaiidromenia valida. X 2S. Fig.<. 7-lo. Liinifds^or laliiuiil( iis. X 33. 



Figs. 1, 2, 4. Cro.ss sections along lines .\, B, C in tig. :>, |il. 11 (anterior end). 

 Figs. 3, 5, (). Through posterior en<l of body. 



Figs. 7, 8, correspond to lines A, B, C in fig. 4, pi. 10 (anteiior ind). 



Fig. 10. Chlorogogue or eoncrenient hearing cells of L. taliioideus, from sides of venlial sinus 

 X 555. 



Fig. 11. Section through brain. 



Fig. 12. Hypodermis of I>. lalpoideus. X 255. 



Fig. 13. Section through heart and ])ericardiuni. X 50. 



